iavf: Add __IAVF_INIT_FAILED state

This commit adds a new state, __IAVF_INIT_FAILED to the state machine.
From now on initialization functions report errors not by returning an
error value, but by changing the state to indicate that something went
wrong.

Signed-off-by: Jakub Pawlak <jakub.pawlak@intel.com>
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>